This stunning gothic ruin was a casualty of the Indiana steel industry crash.

This old steel industry company town has a tradition of parking cars on the sidewalk so people can walk in the narrow streets.

This urban drawbridge gained eternal pop culture fame when the Blues Brothers jumped it while it was raised.

All of Chicago's wood-paved streets are long gone but two alleys remain.

A monument to the art of slicing people open.

G.V. Black, the Father of Modern Dentistry, keeps an eternal eye on Chicagoan’s teeth from his perch in Lincoln Park.

The iconic Chicago sculpture hides a beautiful and easily overlooked plaque on the backside.

A little-known subterranean street runs under some of the best-known buildings in Chicago's River North.

This one-room cabin where the young colonel slept during the French and Indian War.

A winding district gerrymandered into the shape of a mantis.

Built by the patriotic residents of Boonsboro in a single day.

This simple convenience store sits on the location where the Ouija board was named—and has a plaque to prove it.

The haunting "Hell House Altar" is one of the few remnants of an abandoned college that has been a magnet for local legends.

A tiny monument to the unsuccessful attempt by Thomas Jefferson to place the prime meridian in Washington.

The iconic D.C. restaurant where the Cuban Missile Crisis was negotiated, now a Walgreens.

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.

A historic arena where the Beatles played their first concert in the U.S.

The most accurate timepiece in the world.

Once the supplier for noteworthy projects like the National Cathedral, this old brickworks now lies abandoned.

A historic ruin just 20 feet away from a busy highway onramp.

A painfully obvious spy house sits right across the street from the Russian Embassy.

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

The only Civil War battle in Washington D.C. took place near this highest natural point in the city.

A wondrous old library overlooking the nation's capital.